Hello,
I am a factory worker (as an example) working 8 hours a day. From 8 h to 16 h. This is a normal working day as we all imagine and understand it.
 Why do teachers (for example a 1st grade teacher) start at 8 - 8:20 (depending on the solo to solo and solo schedule) and finish at 1245 ? That is to say, he works 4 hours.
Furthermore, roughly they have 2 months of summer holidays, then 4 times a year a week of holidays, I don't know if they have the same as the above employees in the factory the legal holiday of 25 days a year, I hope they don't have that because it would be a bit ridiculous to all the other tax-paying workers....
 Then they go on strike etc...
I propose that teachers work 8 hours a day, that is to say, actually, that they are in salt for 8 hours a day.